14 DAY TRIAL // Just a month after the attack of an escaped tigress at San Francisco ended with the death of three teenagers, a new research published in the journal "Brain, Behavior, and Immunity," shows that cats become enraged exactly the same way as humans.
Enraged cats react by hissing, arching their back, retracting their ears, extending their claws and fur. In humans, the rage is nothing less dangerous, as it can be connected with highly unforeseeable behaviors, like road rage.
"In road rage, the person never thinks about what he is doing but just acts in the way he does because he feels that he has been threatened by someone else and the impulsive behavior represents a way by which he can protect himself from such a threat. In reality, his actions are usually much more dangerous to him than to the person whom he perceived cut him off on the road," co-author Allan Siegel, a professor in the Department of Neurology & Neurosciences at New Jersey Medical School in Newark, told Discovery News.
The anger center had been discovered in the hypothalamus, a nucleus encountered in the middle of the brain. Siegel's team artificially induced anger in 10 adult female cats via electrical stimulation of their hypothalamus. When the team exposed the cats' hypothalamus to a protein called interleukin, this boosted their rage.
"The protein somehow attaches to a serotonin receptor," said Siegel.
Serotonin, the "happiness hormone", gives a relaxation feeling and inhibits many human (and animal) behaviors, from sleep to vomiting, sex and aggressiveness. The interleukin binds to serotonin or to serotonin receptors, and this activates neurons normally inhibited by serotonin.
When neurons discharge at a high rate, the individual gets anxious and falls into a defensive rage. This new information could help the synthesis of drugs targeting rage crisis. Drugs like cocaine, but alcohol too, are believed to activate the hypothalamus. Hypothalamus disorders may cause rage crises as well.
But "there was nothing wrong with the brain of the tiger that attacked the teenagers. Because wild cats are very territorial, the zoo tiger felt threatened and acted aggressively in response, as it would have done in the wild if faced with intruders," said Siegel.